340161-32-2Relevant articles and documents
Chiral lithium amido sulfide ligands for asymmetric addition reactions of alkyllithium reagents to aldehydes
Granander, Johan,Sott, Richard,Hilmersson, Goeran
, p. 439 - 447 (2007/10/03)
Six chiral amino sulfides have been synthesised from the amino acids phenylalanine, phenylglycine and valine. These amino sulfides were used as chiral ligands in the asymmetric addition of n-butyllithium and metyllithium to various aldehydes at low temperatures. The highest stereoselectivities were obtained with benzaldehyde, resulting in 1-phenyl-1-pentanol and 1-phenyl-1-ethanol in enantiomeric excesses of >98.5 and 95%, respectively. These stereoselectivities were significantly higher than those induced by the ether analogues.
New chiral auxiliaries for the construction of quaternary stereocenters by copper-catalyzed Michael reactions
Christoffers, Jens,Mann, Alexander
, p. 2752 - 2754 (2007/10/03)
The construction of quaternary stereocenters with 95-99% ee at ambient temperatures can be achieved by a copper-catalyzed Michael reaction with the application of α-amino acid amides as chiral auxiliaries [Eq. (1)]. These amides can be obtained in a few steps from the α-amino acids with standard transformations and, after the Michael reaction, they can be quantitatively recovered. Exclusion of water and oxygen is not necessary.